Low birthweight is a risk factor for later adverse health. Here the impact of placentally-mediated prenatal growth-restriction followed by postnatal nutrient abundance on growth, glucose metabolism and body composition was assessed in both sexes at key stages from birth to mid-adult life. Singleton-bearing adolescent dams were fed control or high nutrient intakes to induce normal or growth-restricted pregnancies, respectively. Restricted lambs had ~40% reduced birthweight. Fractional growth rates were higher in restricted lambs of both sexes predominantly during suckling/juvenile phases. Thereafter, rates and patterns of growth differed by sex. Absolute catch-up was not achieved and restricted offspring had modestly reduced weight and stature at mid-adulthood necropsy (~109 weeks). Dual-energy X-ray absorptiometry revealed lower bone mineral density in restricted versus normal lambs at 11, 41, 64 and 107 weeks, with males>females from 41 weeks onwards. Body fat percentage was higher in females versus males throughout, in restricted versus normal lambs at weaning (both sexes), and in restricted versus normal females at mid-adulthood. Insulin secretion after glucose-challenge was greater in restricted versus normal of both sexes at 7 weeks, and in restricted-males at 32 weeks. In both sexes fasting glucose concentrations were greater in restricted offspring across the life-course, while glucose area-under-the-curve after challenge was higher in restricted offspring at 32, 60, 85 and 106 weeks, indicative of persistent glucose intolerance. Therefore prenatal growth-restriction has negative consequences for body composition and metabolism throughout the life-course with the effects modulated by sex differences in postnatal growth rates, fat deposition and bone mass accrual.
- Journal Article